This invention relates to novel chemical compounds which are formed by a highly unusual reaction mechanism. More particularly, this invention is directed to hexahydropyrimidine derivatives, the structure and formation of which could not have been (and in fact were not) anticipated or understood until the structural and mechanistic investigations by one of us (DJM).
In prior copending application Ser. No. 318,748, filed Mar. 2, 1989 by three of us (JGB, LJC and JVH), the use of certain additive mixtures as stabilizers for middle distillate fuels is set forth pursuant to the concept by such three of us. The additive mixtures of the prior application include a wide variety of Mannich bases. Included within the scope of the such Mannich bases is a new class of Mannich bases, the correct structural formula of which is set forth in the prior application. Such new Mannich bases fall within the scope of a larger class of novel compounds with which this application is concerned. The elucidation of the structures of these particular novel compounds resulted from the structural and mechanistic investigations by the other one of us (DJM).
The Mannich reaction among phenols, formaldehyde and amines is a well-known reaction which has been extensively documented in the literature. However, to the best of our knowledge and belief, the rearrangements and mechanistic aspects involved in the formation of the compounds of this invention are wholly unprecedented. In simple terms, given the identities of the reactants from which the compounds of this invention are made, the course of the reaction and the particular structural make-up of the products of such reaction could not have been predicted on the basis of pre-existing knowledge.